Prostaglandin E isomerase (known as PGE2 synthase also) catalyses the isomerization reaction in which prostaglandin endoperoxide (PGH2), is converted to PGE2. The potent biological activities of PGE2 indicate an important role for prostaglandin E isomerase in the pathogenesis of periodontal disease, progression of the tumor, inflammatory and immune responses. Commercial availability of a purified preparation of mammalian prostaglandin E isomerase should therefore facilitate basic and pharmaceutical research, including studies of factors involved in regulation of PGE isomerase gene expression, development of novel therapeutic agents for the treatment of cancer, diabetes, and the pathogeny of certain forms of schizophrenia. In Phase I, we will purify prostaglandin E isomerase from ram seminal vesicles (RSV), determine conditions for enzyme assay and storage, and evaluate the cofactor requirements of the purified protein. In Phase II research, we will employ affinity chromatography and immunoaffinity chromatography to purify the enzyme to homogeneity. The purified enzyme will be used for the production of polyclonal antibodies and amino acid sequencing. Polyclonal antibodies and oligonucleotide probes based on a partial amino acid sequence will be prepared and used as reagents for the identification and isolation of molecular clones of the prostaglandin E isomerase gene and its further characterization.